2 items are filed under this topic.








Cardinality of sets 
20011119 

From Tania:
 Show that the cardinality of P(X) (the power set of X) is equal to the cardinality of the set of all functions from X into {0,1}.
 Show that (the cardinality of the natural numbers set) N = NxNxN.
 Show that the cardinality of the set of prime numbers is the same as the cardinality of N+
Answered by Walter Whiteley. 





Diagonals in a polygon 
19960618 

From Steven: How many diagonals are there in a polygon? Answered by Denis Hanson. 


